Tread Base for Treadmill

ABSTRACT

A tread base includes a tread base frame unit with front and rear belt wheel sets arranged at opposing front and rear sides thereof, and an endless running belt mounted around the front and rear belt wheel sets and having slats transversely arranged on the outer perimeter thereof in a parallel manner. The running belt includes a plurality of movable sliding rollers respectively mounted at the opposing left and right ends of the slats. The tread base frame unit includes two smoothly arched sliding tracks longitudinally arranged in parallel for supporting and guiding the movable sliding rollers of the running belt to enhance the moving stability of the running belt, preventing breaking of the slats of the running belt, avoiding danger and prolonging the lifespan of the tread base.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to treadmill technology and moreparticularly, to a tread base for treadmill, which has two slidingtracks arranged on a tread base frame unit for supporting and guidingthe movement of a movable sliding roller-equipped running belt toenhance the moving stability of the running belt, preventing breaking ofslat components of the running belt and prolonging the lifespan of thetread base.

2. Description of the Related Art

US2012/0010053A1 discloses a manually operated treadmill, which includesa treadmill frame having a front end and a rear end opposite the frontend, a front shaft rotatably coupled to the treadmill frame at the frontend, a rear shaft rotatably coupled to the treadmill frame at the rearend, and a running belt including a curved running surface upon which auser of the treadmill may run. The running belt is disposed about thefront and rear shafts such that force generated by the user causesrotation of the front shaft and the rear shaft and also causes therunning surface of the running belt to move from the front shaft towardthe rear shaft. The treadmill is configured to control the speed of therunning belt to facilitate the maintenance of the contour of the curvedrunning surface.

However, this design of treadmill is still not satisfactory in functionand has drawbacks as follows:

1. The running belt is comprised of a plurality of slat components; whenthe user is running on the running belt, the left and right bearingsupport frames supports the opposing left and right sides of the runningbelt, however, a large part of each slat component is suspended in theopen air without support, and thus, the slat components can break easilyupon a heavy impact force, causing accidents.

2. The bearings (non-sliding rollers) at the opposing left and rightsides of the tread base frame unit are rotatable but not movable withthe running belt, unable to enhance the moving smoothness of the runningbelt.

3. The left and right bearing support frames must be precisely processedto provide precision bearing holes for the mounting of respectivebearings; if the machining tolerances of the bearing holes are slightlydifferent, the sliding smoothness of the running belt can be reduced,leading to a defective product; the machining of the bearing holes andthe installation of the bearings are complicated and need much labor andtime, greatly increasing the manufacturing cost of the treadmill.

Further, the technique of using a conveyor belt to mate with belt wheelsin a treadmill for enabling a runner to experience bumps and depressionswhen running is the known prior art technique. U.S. Pat. No. 1,211,765,U.S. Pat. No. 4,614,337, U.S. Pat. No. 5,470,293 and U.S. Pat. No.5,577,598 disclose similar technical contents.

SUMMARY OF THE INVENTION

The present invention has been accomplished under the circumstances inview. It is therefore the main object of the present invention toprovide a tread base for treadmill, which has sliding tracks arranged onthe tread base frame unit for supporting and guiding the movement of themovable sliding rollers of the running belt, enhancing the movingstability of the running belt.

It is another object of the present invention to provide a tread basefor treadmill, which has sliding tracks arranged on the tread base frameunit for supporting and guiding the movement of the movable slidingrollers of the running belt, so that the impact force produced duringrunning of the user on the running belt can be distributed through themovable sliding rollers of the running belt to the sliding tracks of thetread base frame unit, preventing breaking of the slats of the runningbelt, avoiding danger and prolonging the lifespan of the tread base.

It is still another object of the present invention to provide a treadbase for treadmill, which facilitates the fabrication and installationof the movable sliding rollers and the sliding tracks without tediousprecision dimensional tolerance proofreading works, saving muchfabrication and installation labor and time and lowering themanufacturing cost.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is an oblique elevational view of a running belt of a tread basefor treadmill in accordance with the present invention.

FIG. 2 is a side plain view of the running belt shown in FIG. 1.

FIG. 3 is an exploded view of the tread base frame unit and running beltof the tread base in accordance with the present invention.

FIG. 4 is an exploded view of the present invention, illustrating thetread base frame unit assembled with the front and bear belt wheel setsbefore mounting of the running belt.

FIG. 5 is an oblique elevational view of the tread base in accordancewith the present invention.

FIG. 6 is a side plain view of the present invention, illustrating therunning belt mounted around the main tread base frame of the tread baseframe unit.

FIG. 7 is a schematic drawing of the present invention, illustrating therelationship between one slat and the respective movable sliding rollersin the respective sliding tracks.

FIG. 8 is a sectional end view of FIG. 7.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1-8, a tread base for treadmill in accordance withthe present invention is shown. The tread base comprises:

a tread base frame unit 1, comprising a main tread base frame 10 (seeFIG. 3 and FIG. 4) for holding a front belt wheel set 2 and a rear beltwheel set 3 respectively at opposing front and rear sides thereof, aleft bracket 12 and a right bracket 13 respectively affixed to opposingleft and right sides of the main tread base frame 10 with fasteningmeans or by welding;

a front belt wheel set 2 comprising a front wheel axle 21 (see FIG. 3and FIG. 4) transversely pivotally mounted in the front side of the maintread base frame 10 and two front belt wheels 22 respectively mounted atopposing left and right ends of the front wheel axle 21;

a rear belt wheel set 3 comprising a rear wheel axle 31 (see FIG. 3 andFIG. 4) transversely pivotally mounted in the rear side of the maintread base frame 10 and two rear belt wheels 32 respectively mounted atopposing left and right ends of the rear wheel axle 31;

a running belt 4 see FIGS. 1-4) comprising an endless wide band belt 41mounted around the opposing front and rear sides of the main tread baseframe 10, a plurality of slats 42 respectively fixedly arranged aroundan outer perimeter of the endless wide band belt 41 in a parallel mannerat a predetermined pitch, and two endless narrow band belts 43respectively fixedly fastened to an inner perimeter of the endless wideband belt 41 at opposing left and right sides and respectively coupledto the respective belt wheels 22,32 of the front and rear belt wheelsets 2,3 so that when a user runs on the slats 42 of the running belt 4,the endless wide band belt 41 and the endless narrow band belts 43 areforced to move and to rotate the belt wheels 22,32 of the front, rearbelt wheel sets 2,3;

wherein:

the running belt 4 further comprises at least one movable sliding roller44 mounted at each of opposing left and right ends of each slat 42 (seeFIGS. 1-4 and FIG. 6);

the main tread base frame 10 of the tread base frame unit 1 comprisestwo sliding tracks 11 longitudinally arranged in parallel (see FIGS. 3-4and FIGS. 7-8) with respective two opposite ends 112 thereof smoothlydownwardly curving toward a respective lowest middle point 111 toexhibit a smoothly arched profile for supporting and guiding the movablesliding rollers 44 of the running belt 4 to enhance running stability.

Preferably, the running belt 4 further comprises a plurality of pivotblocks 45 respectively mounted at the opposing left and right ends ofthe slats 42 to support the respective movable sliding rollers 44.

Thus, when a user runs on the slats 42 of the running belt 4 to move theendless wide band belt 41 and the endless narrow band belts 43 and torotate the belt wheels 22,32 of the front, rear belt wheel sets 2,3, themovable sliding rollers 44 are rotated along the respective slidingtrack 11 of the tread base frame unit 1, enhancing the stability of themovement of the running belt 4. At the same time, the impact forceproduced during running of the user is distributed through the movablesliding rollers 44 of the running belt 4 to the sliding tracks 11 of thetread base frame unit 1, preventing breaking of the slats 42 of therunning belt 4, avoiding danger and prolonging the lifespan of the treadbase. Further, the fabrication and installation of the movable slidingrollers 44 and the sliding tracks 11 are simple and convenient withouttedious precision dimensional tolerance proofreading works, saving muchfabrication and installation labor and time and lowering themanufacturing cost.

In general, the invention achieves the effects as follows:

1. The sliding tracks 11 are smoothly arched to support and guide themovable sliding rollers 44 during movement of the running belt 4,enhancing the moving stability of the running belt 4.

2. The impact force produced during running of the user can bedistributed through the movable sliding rollers 44 of the running belt 4to the sliding tracks 11 of the tread base frame unit 1, preventingbreaking of the slats 42 of the running belt 4, avoiding danger andprolonging the lifespan of the tread base, further, the fabrication andinstallation of the movable sliding rollers 44 and the sliding tracks 11are simple and convenient without tedious precision dimensionaltolerance proofreading works, saving much fabrication and installationlabor and time and lowering the manufacturing cost.

What is claimed is:
 1. A tread base for treadmill, comprising: a treadbase frame unit comprising a main tread base frame for holding a frontbelt wheel set and a rear belt wheel set respectively at opposing frontand rear sides thereof, and a left bracket and a right bracketrespectively affixed to opposing left and right sides of said main treadbase frame; a front belt wheel set comprising a front wheel axletransversely pivotally mounted in the front side of said main tread baseframe and two front belt wheels respectively mounted at opposing leftand right ends of said front wheel axle; a rear belt wheel setcomprising a rear wheel axle transversely pivotally mounted in the rearside of said main tread base frame and two rear belt wheels respectivelymounted at opposing left and right ends of said rear wheel axle; arunning belt comprising an endless wide band belt mounted around theopposing front and rear sides of said main tread base frame, a pluralityof slats respectively fixedly arranged around an outer perimeter of saidendless wide band belt in a parallel manner at a predetermined pitch,and two endless narrow band belts respectively fixedly fastened to aninner perimeter of said endless wide band belt at opposing left andright sides and respectively coupled to the respective said belt wheelsof said front belt wheel set and said rear belt wheel sets; wherein:said running belt further comprises at least one movable sliding rollermounted at each of opposing left and right ends of each said slat; saidmain tread base frame of said tread base frame unit comprises twosliding tracks longitudinally arranged in parallel for supporting andguiding said movable sliding rollers of said running belt.
 2. The treadbase for treadmill as claimed in claim 1, wherein each said slidingtrack has two opposite ends thereof smoothly downwardly curving toward amiddle point thereof to exhibit a smoothly arched profile.
 3. The treadbase for treadmill as claimed in claim 1, wherein said running beltfurther comprises a plurality of pivot blocks respectively mounted atthe respective opposing left and right ends of said slats to support therespective said movable sliding rollers.
 4. A tread base for treadmill,comprising: a tread base frame unit having a front side and a rear sideopposite to said front side; a front belt wheel set comprising a frontwheel axle transversely pivotally mounted in the front side of said maintread base frame and two front belt wheels respectively mounted atopposing left and right ends of said front wheel axle; a rear belt wheelset comprising a rear wheel axle transversely pivotally mounted in therear side of said main tread base frame and two rear belt wheelsrespectively mounted at opposing left and right ends of said rear wheelaxle; a running belt comprising an endless wide band belt mounted aroundthe opposing front and rear sides of said main tread base frame, aplurality of slats respectively fixedly arranged around an outerperimeter of said endless wide band belt in a parallel manner at apredetermined pitch, and two endless narrow band belts respectivelyfixedly fastened to an inner perimeter of said endless wide band belt atopposing left and right sides and respectively coupled to the respectivesaid belt wheels of said front belt wheel set and said rear belt wheelsets; wherein: said running belt further comprises at least one movablesliding roller mounted at each of opposing left and right ends of eachsaid slat; said tread base frame unit comprises two sliding trackslongitudinally arranged in parallel for supporting and guiding saidmovable sliding rollers of said running belt.
 5. The tread base fortreadmill as claimed in claim 4, wherein each said sliding track has twoopposite ends thereof smoothly downwardly curving toward a middle pointthereof to exhibit a smoothly arched profile.
 6. The tread base fortreadmill as claimed in claim 4, wherein said running belt furthercomprises a plurality of pivot blocks respectively mounted at therespective opposing left and right ends of said slats to support therespective said movable sliding rollers.